You are confusing MPEG the ISO working group with MPEG-LA the private company of lawyers. ISO has nothing to gain from patent trolling, they are financed by the purchase of their standards. MPEG is doing the exact same thing they have since 1988. That's saying nothing of the ITU, which is equally involved in this spec.
I was referring to the MPEG-LA (the patent related entity) not to the ISO working group. The new spec is coming from the technical participants, whose patents are managed by MPEG-LA. The patents of the resulting codec will be obviously managed by MPEG-LA as before, and they don't want the situation when H.264 patents will expire and the industry would get away from the lock in into their closed codec. They want the closed part to persist.
The intentions of improving technical side of the codec are also there, but it comes along with expanding the time of the patent grip on the whole thing.
ISO itself has nothing to gain from the patent setup for the MPEG specs, but their members sure do. If you haven't read http://lists.xiph.org/pipermail/theora/2010-April/003769.htm... before, you may want to. It's an interesting perspective on the MPEG standards process.
